The present application relates generally to interconnect structures for microelectronic devices, and more particularly to structures and methods for improving device reliability and performance by the selective incorporation of dopants into conductive lines.
Total on-chip interconnect lengths have been increasing exponentially with technology scaling. As a result, interconnect-driven design is an evolving trend in state-of-the-art integrated circuits. Copper-based interconnect technology is expected to meet some of the challenges of technology scaling. However, copper interconnects still pose reliability concerns due to electromigration-induced failure over time.
The alloying of copper (Cu) interconnects with dopants such as manganese (Mn) has been shown to improve electromigration reliability. However, the addition of manganese significantly increases interconnect resistance, which negatively impacts performance.
Thus, there is an ongoing need for methods and structures to improve electromigration reliability without adversely affecting device performance.